Roof drain



L. BLENDEJRMANN ETAL 3,469,699

ROOF DRAIN Filed Oct. 23, 1967 Fla-2 SNR mmw TA muw VR NE E6 0 8 84 a L mw 0 we LN ATTORNEYS United States Patent US. Cl. 210-166 5 Claims ABSTRACT OF THE DISCLOSURE A controlled flow roof drain comprised of a bowl and an annular flashing clamp plate forming a drain body, a dome grate over an inlet through the plate, and an ad ustable flow control, open top barrier within dome; the barrier comprising in elfect a vertically plural slotted sleeve about the inlet integral with the plate providing rectangular weir openings between fixed vanes, and a similarly slotted rotationally shiftable collar surrounding the sleeve having an end ring supported on the fixed vanes with movable dependent vanes defined between the collar slots; with a floW-index-marked bolt-and-slot connection of the collar ring to the fixed vanes for rotational adjustment of 'vane overlap setting the flow controlling weir area for heads up to the level overflowing the barrier top.

The present invention relates generally to controlled flow roof drains, and more particularly to a roof drain incorporating an adljustable weir structure readily producible by metal casting procedures. Specifically the subject matter hereinafter disclosed represents in effect a continuation-in-part of the co-pending US. application Ser. No. 628,658, filed Apr. 5, 1967; and for certain purposes represents a specific improvement over forms of drains disclosed in that pending application.

The drain of the present invention is particularly adapted to and intended for roof drainage systems, be-

coming increasingly important in modern building design,

which are characterized by reliance upon so-called roof storage of rain fall for rational minimization of drains and of capacity of drain leaders and lines to be installed in the building, by so controlling the actual rate of runoff to the available outside disposal facilities as to avoid overloading the same, especially where such facilities are public sewers.

The present invention provides a barrier structure surrounding a drain inlet to establish a maximum height of water for roof storage, up to which height adjustable barrier weirs by selected setting control and determine the run-olf rate for the head of water accumulated or stored. The barrier is comprised of relatively simple structure and elements readily fabricated as, for example, metal castings by conventional techniques. The aforegoing abstract has set forth the general arrangement of the specific embodiment of the invention disclosed in the drawings and the specific description thereof hereinafter given. However, it is to be understood that certain aspects of the invention might advantageously be embodied in a drain for other than a roof environment, in a drain lacking a dome-type grating or having a side rather than bottom outlet, or in a one-piece body type drain in contrast with the one specific embodiment hereinafter described and shown in the drawings wherein:

FIG. 1 is a vertical section of a drain embodying the present invention, the section being somewhat irregularly taken in part;

FIG. 2 is a fragmentary sectional detail taken as indicated at the line 22 in FIG. 1; and

3,469,699 Patented Sept. 30, 1969 ice FIG. 3 is a further fragmentary detail taken as indicated at the line 3-3 in FIG. 2.

The general drain arrangement wherein the invention is shown embodied in the drawing is of a known roof drain type comprised of a two-piece drain body B, including a cast metal bowl-shaped main bottom part 10 with a bottom outlet to which is caulked, or as here shown, threadedly engaged, a vertical drainage leader of drain pipe D, and a top annular metal plate part 11; and, for catching and retaining debris, a slotted type grate or strainer dome A having generally vertical side and horizontal top slots affording a generous total flow area therethrough to the central plate opening 14 as the drain body inlet. Though these and other parts of the drain are represented or described as metal, plastics may be used in accordance with established design considerations.

Conventionally, the top surface of the integral bowl flange portion 10a and the bottom of the plate 11 have cooperating formations clamping therebetween roofing or flashing sheet material F when the plate is secured to the bowl by a plurality of bolts 12; and the upper perimeter of the plate has integrally formed thereon a vertically slotted circumferential gravel stop 11a also serving to locate the dome A with bottom rim received therein on the top plate. Conventional means for securing the drain in the environment of use are not shown.

It may be observed that, within the gravel stop downwardly slotted to the flat top area of plate 11, the circumferential bottom edge or rim of the dome preferably rests on three or more equi-spaced integral pads on the top of plate 11, for example, at the locations of dome securing socket head cap screws through the rim threaded into the top plate at such pads; thereby providing a large circumferential extent of thin drainage slots beneath the dome edge, to avoid interference of final drainage through the grlavel stop across the flat top areas of plate 11 to the in ct.

However, the clamping top plate 11 also serves to mount underneath the dome a water flow control barrier structure indicated as a whole by the general reference character S provided in accordance with the invention to control the flow through the drain of water from the surrounding drainage area.

In barrier S, a plurality of like-shaped upright fixed vanes 84, here four, coaxially arcuate in cross-section but upwardly tapering for draft, are equi-spaced about the drain inlet 14 in, and integrally cast with, clamping plate 11, to define therebetween four generally rectangularopen-top Weirs or drainage flow control openings; but each fixed vane on its concave inner face has a vertical longitudinal central semi-circular tapering rib 84a for reinforcement and other purposes to be described. This fixed portion of the barrier may be considered an integral sleeve or roughly cylindrical flange about the inlet, having vertical substantially rectangular open end slots running down to the level of the flat area of 11.

On such fixed sleeve, as a weir-size adjusting structure of S, there is an adjustable vane collar rotationally shiftably supported, shown in an external embracing rather than an internal disposition possible with corresponding shape changes, and comprising as integral structure a set of unitarily movable like vanes 85 dependent to plate 11 from and integral with a fiat top rim or ring 85a overlaying the generally flat top ends of the fixed vanes 84. The movable vanes are equal in number to and have substantially the same angular extent as the fixed vanes, so that rotational shifting of the collar, changing the vane overlap, changes the effective weir openings; while at all time providing a large overflow opening at the top of the barrier collar.

The fixed and shiftable vanes taper in cross-section both in radial thickness and arcuate length as may be required to afford necessary draft for casting fabrication; and the disclosed drain form advantageously is adapted to casting roduction by green sand molding without need of cores. The external ihced and internal movable surfaces are complementary in draft taper and armate shape as shown in FIG. 2. The maximum rectangular opening available when the movable vanes entirely overlap, except for the divergency from verticality and rec tangularity due to draft taper, appears at the center of FIG. 1, designated Wm between solid lines for one weir; a diminished opening Ws designated for a dashed shifted position of movable vane.

The adjustable vane collar, supported on the fixed vane ends as bearing surfaces, is secured relative to the top plate on at least one, preferably two diametric or all four fixed vanes, by a respective screw 86 passed through an arcuate slot in the flat ring portion 85a and threaded into the top end of the underlying fixed vane at rib enlargement 84a as shown in FIGS. 1 and 3.

Preferably as shown in FIG. 3 screw 86 is a vandalproof type flat head machine screw, with the cooperating arcuate slot having, as appears at 85b in FIG. 3, in its upper part a triangular cross-section to accommodate the conical shape of the screw head, and therebeneath a series of intersecting bolt shank receiving bores for stepwise or incremental shifting of the collar and corresponding weir size changes; there being marked, for example, by casting integrally in ring 85, a corresponding series of index legends 87, here alphabetical, as a code for corre sponding ranges of flow rates available at corresponding successive positionings of the collar relative to the fixed vanes.

In this arrangement, of course, the height, e.g., 5 inches, from the fiat top area of the plate 11, to be located substantially at the level of or slightly below the surrounding roof surface area, up to the top surface of the ring 85a as the effective level of its central aperture as a barrier overflow opening, determines the height of the maximum roof storage head of water before overflow occurs to be restrained only the size of the ring opening.

Additionally to the use of the vandal-proof machine screws, the bolted dome secnrement serves to discourage tampering with the drain setting.

We claim:

1. A roof-drain or like drain comprising: a bowl-shaped body having a top inlet and a lower outlet adapted to be 4 connected to a drainage line; an open-top barrier structure mounted on the body and surrounding said inlet; said barrier structure including a vertically slotted, opentopped approximately cylindrically round flange surrounding said inlet and at its bottom joined to the top of said body, a rotationally adjustable collar coaxially disposed relative to and vertically slotted corresponding to said flange, said collar including a ring extending radially over the top end of the said flange and affording a central barrier top overflow inlet, and means securing said collar relative to the said flange, whereby rotational collar shifting varying the extent of coincidence of collar and flange slots changes the slot area effective for weir flow control of water into the drain for heads of water up to the level of said ring opening.

2. A drain as described in claim 1, said securing means comprising a screw-and-slot connection comprising an arcuate slot-like formation in said ring and a screw ther through threaded into a threaded portion on the top end of said flange.

3. A drain as described in claim 2, wherein said flange is integral with the top portion of said body, said collar and said flange having cooperating respective surfaces being substantially complementary and in sliding contact; said arcuate formation including a series of recesses spaced therealong and respectively adapted to receive a head portion of said screw as a weir-size indexing means.

4. A drain as described in claim 1, wherein said collar is disposed externally of said flange.

5. A drain as described in claim 1, wherein said body is a two-piece body comprised of a lower main bowl portion and a top plate portion cooperatively bolted thereto as a flashing clamp and centrally apertured to provide said inlet; said flange integral with said plate portion; said collar and said flange having cooperating respective surfaces substantially complementary for sliding water sealing contact.

References Cited UNITED STATES PATENTS 3,349,917 10/1967 Strickland 210-164 3,357,561 12/1967 Schmid et a1 210-163 REUBEN FRIEDMAN, Primary Examiner T. A. GRANGER, Assistant Examiner 

